Now, in the blood, each red blood cell has millions of hemoglobin proteins.

在血液中，个血红细胞都有数百万血红蛋白。

And each of those hemoglobins can bind to four oxygen molecules.

而一个血红蛋白能与4个氧分子结合。

They are made in the bone marrow and contain a special ion-containing protein called hemoglobin.

它们是在骨髓中形成，含有一种叫做血红蛋白特殊含离子蛋白质。

These disorders are caused by genetic mutations that prevent the normal production of hemoglobin.

这些疾病是由阻止血红蛋白正常产生基因突变。

So each hemoglobin can carry four oxygen molecules when it's fully saturated.

所以在饱和时，一个血红蛋白可以携带四个氧分子。

The illnesses are caused by errors in the gene for hemoglobin.

这些疾病是由血红蛋白基因缺陷。

But the fact is, hemoglobin's affinity for oxygen isn't always the same.

但事实是，血红蛋白对氧气亲和力并不总是一样。

Normally, hemoglobin is made up of four globin chains, each bound to a heme group.

正常情况下，血红蛋白由4条珠蛋白链组成，条珠蛋白链都与一个血红素基团结合。

They also have a special type of hemoglobin, the molecule in the blood that transports oxygen.

他们同时有着一种特殊血红蛋白，这种分子在血液中负责运输氧气。

Carbon monoxide and oxygen compete to bite hemoglobin in your blood, which stresses the circulatory system.

一氧化碳和氧气争先恐后地与血液中血红蛋白结合，这给血液循环系统带来了压力。

Now your hemoglobin is known as oxyhemoglobin, or HbO2.

现在你血红蛋白被称为氧合血红蛋白，或 HbO2。

These four globin chains combine in different ways to give rise to different kinds of hemoglobin.

这四种珠蛋白链以不同方式结合，形成不同类型血红蛋白。

If there are three defective alpha genes, there's moderate disease, called hemoglobin H, or HbH, disease.

如果有3个α基因异常，则出现中度地中海贫血，即血红蛋白H病（HbH病）。

It says that an increase in carbon dioxide results in hemoglobin proteins releasing oxygen into the tissues.

当血液中二氧化碳增多时，血红蛋白会把红细胞绑定氧气释放到人体组织中去。

Their hemoglobin is much stickier for oxygen than ours and can pick oxygen up even when it's scarce.

它们血红蛋白比我们更加粘，能够在氧气很稀薄情况下也能进行收集。

When red blood cells do not have enough hemoglobin, oxygen doesn't get to all parts of the body.

当红细胞没有足够血红蛋白时，氧气就无法到达身体各个部位。

To treat sickle cell disease, researchers used CRISPR to make the body produce the fetal form of hemoglobin.

为了治疗镰状细胞病，研究人员使用 CRISPR 使身体产生胎儿形式血红蛋白。

The modified cells are then infused back into the body to allow it to start producing functioning hemoglobin.

然后将修改后细胞注入体内，使其开始产生功能正常血红蛋白。

But, for example, if I looked at, fetal hemoglobin relinquishes that oxygen at lower oxygen tensions.

但是，举个例子，如果我看到，胎儿血红蛋白在较低氧张力下放弃氧气。

One of the adaptations that the body makes after it's been at high altitude is to make more hemoglobin.

在高海拔地区，身体其中一个适应就是制造更多血红蛋白。